FastText

fasttext.cc

void FastText::trainThread(int32_t threadId) {
  std::ifstream ifs(args_->input);
  utils::seek(ifs, threadId * utils::size(ifs) / args_->thread);

  Model model(input_, output_, args_, threadId);
  if (args_->model == model_name::sup) {
    model.setTargetCounts(dict_->getCounts(entry_type::label));
  } else {
    model.setTargetCounts(dict_->getCounts(entry_type::word));
  }

  const int64_t ntokens = dict_->ntokens();
  int64_t localTokenCount = 0;
  std::vector<int32_t> line, labels;
  while (tokenCount_ < args_->epoch * ntokens) {
    real progress = real(tokenCount_) / (args_->epoch * ntokens);
    real lr = args_->lr * (1.0 - progress);
    if (args_->model == model_name::sup) {
      localTokenCount += dict_->getLine(ifs, line, labels);
      supervised(model, lr, line, labels);
    } else if (args_->model == model_name::cbow) {
      localTokenCount += dict_->getLine(ifs, line, model.rng);
      cbow(model, lr, line);
    } else if (args_->model == model_name::sg) {
      localTokenCount += dict_->getLine(ifs, line, model.rng);
      skipgram(model, lr, line);
    }
    if (localTokenCount > args_->lrUpdateRate) {
      tokenCount_ += localTokenCount;
      localTokenCount = 0;
      if (threadId == 0 && args_->verbose > 1)
        loss_ = model.getLoss();
    }
  }
  if (threadId == 0)
    loss_ = model.getLoss();
  ifs.close();
}